Reject annotation anchoring when no quote selector found

h/static/scripts/annotator/anchoring/html.coffee

@@ -50,6 +50,11 @@ exports.anchor = (root, selectors, options = {}) ->
       when 'RangeSelector'
         range = selector
 
+  # Assert that there is a quote selector, since otherwise we cannot validate
+  # the rest of the annotation's selectors.
+  if not quote?
+    return Promise.reject(new Error('quote selector not found'))
+
   # Assert the quote matches the stored quote, if applicable
   maybeAssertQuote = (range) ->
     if quote?.exact? and range.toString() != quote.exact

h/static/scripts/annotator/test/integration/anchoring-test.js

@@ -99,4 +99,22 @@ describe('anchoring', function () {
     ],
     expectFail: true,
   }]);
+
+  unroll('should silently fail when an annotation does not have a quote selector', function (testCase) {
+    var annotation = testCase.annotation;
+    var anchored = guest.anchor(annotation);
+
+    return anchored.then(function (result) {
+      assert.deepEqual(result, []);
+    });
+  }, [{
+    annotation: [{
+      target: [{
+        selector: [{
+          type: 'FragmentSelector',
+          value: 't=30,60'
+        }]
+      }]
+    }],
+  }]);
 });